In the course of heat treating wire it is sometimes beneficial to treat the wire in a molten fluid bath. When a molten lead bath is employed for annealing steel wire, elaborate heat control means are employed to maintain a proper lead temperature throughout the length of the bath. The lead bath is contained in an elongated trough. The wire that enters the bath is very hot and the bath quickly heats up as a result of the wire passing through it. One known method of attempting to maintain the lead bath temperature is directing fans at the warmer sections of the bath in an effort to cool them. This method can be inefficient for a number of reasons. Aiming the fan nozzles at specific hot spots is difficult. Even if the nozzles are directed at a specific hot spot, the spot may shift. Depending on the size of the bath, a large number of fans may be required which causes a great deal of power to be used to cool the bath.
Therefore it is desired that another method be used to be able to control temperature in the molten fluid bath.